Reverse Phrenology
by KarotsaMused
Summary: Phrenology: N the study of the shape of the skull, based on the belief that it reveals character and personality. Mugen and Jin try it backwards. Violence and language. MugenJin


A/N: Hello. Wow. Weirdass fic. But I like it 

Disclaimer: Samurai Champloo belongs to its creators. I'm using it without permission and for no profit.

Thanks be to Rune for the beta. Woo! Enjoy.

* * *

"Do what you like with your women. I want to beat the _fuck_ out of you."

No. That wasn't how he said it.

"I want to _beat_ the fuck out of you."

That was it.

Jin is a swordsman. He was never shown how to use his fists, elbows, teeth, because his weapons are his fangs. He is learning how to survive in the moments without them under too-watchful eyes, learning all over again the taste of bile and adrenaline.

Mugen reeks of it.

On the surface, Mugen smells of an empty stomach and the hay they'd slept in so many hours before, of sweat and sunlight and old dirt and the blood behind his ears.

Jin has no space to draw his sword but enough power to bring his arm up and jam Mugen in the hollow of his throat.

He coughs bloody and heaves for breath on the floor, both hands wrapped around his neck, his eyes open but unseeing. Jin rubs his knuckles and steps around Mugen, almost delicately. A callused, brown hand grabs his ankle and Mugen rolls with him, following Jin's movement until he stops. He spins violently, ripping Jin's leg from under him. Jin has to land on his hands to stop his fall and his glasses slide off, lenses saved only by the strength of the frames as they skitter away.

Mugen, still coughing, still wheezing, yanks Jin's leg and pulls him down until his hands find purchase on his belt. Mugen hefts himself onto his knees and flips Jin onto his back, but before a reared fist can land, Jin has his sword drawn and hovering steadily over Mugen's collarbone, reflecting the shadows of a growing bruise.

"No fair," Mugen growls, one hand reflexively going for his own sword and the other wrapping around Jin's wrist, thumb tracing the tendons until he pushes in and twists, forcing Jin's hand open. The sword rests on Mugen's shoulder, propped by the heel of Jin's hand, and for an instant he lets the cold metal stay. It draws one fine line through his skin when Mugen forces Jin's wrist to the floor before it drops blade-first onto Jin's stomach. Before Jin can get his other hand onto it, Mugen has the flat of the blade resting almost friendly under Jin's jaw. He gets a knee between Jin's and presses down hard on the fabric he catches.

It is not enough. Jin throws his knee up and grits his teeth when Mugen jerks forward and his own sword digs into his jaw to the bone.

Mugen rolls off, letting go of the sword and clutching at his balls, choking on his swearwords as Jin reclaims his weapon and sheaths it, curbing the sudden, savage impulse to kick Mugen in the face on his way out. His glasses are resting by the doorway, unscratched, and he replaces them on his nose without breaking his stride. He needs bandages before Fuu finds him and begins her daily conniption. Sometimes it's almost amusing, how surprised she is that he and Mugen get hurt.

This isn't the first challenge issued, and certainly won't be the last. Jin knows, because they promised not to kill one another and if nothing else there is a sort of honor in not lying to a little girl. Instead they grapple and leave skin burns on one another, Mugen teaching and Jin observing, learning his opponent's weak spots and his own and just how painful a weapon his soft body can be.

He hadn't resorted to such dishonorable means of escape since the first time. Mugen had almost broken his glasses then, had left fingerprint bruises on his bare chest and had torn through all vestiges between them, leaving Jin on his back on the hardwood floor to be clothed only in firelight from the lanterns. That time, he'd felt the shock of impact ripple down his own leg and Mugen hadn't walked the same way for days. After that, Jin got better, and the tinge of panic ebbed away.

Mugen learned from Jin never to kick his sandals off if he didn't want his nose broken with his own shoe, and Jin learned that his glasses were stronger than he thought they were. Mugen knows how Jin ties the knots at his belt and Jin knows Mugen is weaker on his left side. Mugen has tasted Jin's blood and seen him with his hair down and catching on his scrapes. Jin has known Mugen's teeth on his wrist, his shoulders, his chest, his neck. Mugen can tell the difference between when Jin is tiring or resting up for a surprise attack. Jin knows how long it takes for Mugen to tire.

Jin returns to him after having his neck bandaged, sitting by the doorway with a roll of bandages in his pocket. He pitches it to Mugen, the lazy sprawl on the floor not hiding the wince still tugging at his features. Jin does not watch as Mugen shrugs out of his shirt and wraps the bandage under his arm, over his neck, under his arm, over his neck. The process is slow, patient, one of the only things Mugen ever takes the time to do properly. He covers the bleeding wound and then, because he has leftovers, wraps the bandages more securely around the dark, ugly bruise cupping his Adam's Apple.

"I doubt this dissuades you from trying again," Jin murmurs, taking his glasses off and wiping the lenses on his knee.

Mugen snorts and it turns into a choked-off cough. "I'll stop when I've won." Mugen lays back on the floor, using his shirts as a pillow, and probes at the bandages over his bruise.

"I'll slay you before I submit to you."

Mugen looks over to Jin and grins, and the blood caked around his teeth turns them brown. "Anything else is stuff for the second date. I don't plan that far and I ain't dying."

Jin leans against the doorframe and looks out into the night, ignoring Mugen and the raspy sound of his breathing. The bullfrogs and crickets, mice and snakes all mute their noises if only so Jin can only focus on Mugen behind him. Mugen moves softer and faster than he realizes, but only comes to sit beside him and breathe the copper-vomit smell of old blood over Jin's shoulder.

"You shouldn't move," Jin admonishes, not looking at him but knowing acutely how close Mugen is.

"Been through worse. You're gonna bleed out." Mugen reaches up and presses his fingers to the bandages under Jin's chin and brings his hand back bloody as evidence. His touch stung but its gentleness and suddenness steal Jin's breath.

"I won't."

Mugen grunts and shuffles back toward his shirts, resting his head on his arm on his shirts with his back to Jin. And then he rolls onto his back, unwraps his neck, tears the bandage with his teeth, and throws the wad at Jin, leaving his bruise exposed.

"Fucking shitty way to die."

Mugen rolls over and falls asleep. Jin listens to him snoring as he works the knots on his bandages.

* * *

Jin finds himself losing even as he looks down at Mugen. Even as Mugen's head hits the ground and kicks up dust, Jin is losing to him. Mugen groans at the crack to his skull and laughs while his vision clears, pulling his own hands further up over his head and forcing Jin down over him. Mugen writhes upward, grinding his hips against Jin's and getting a leg up around his waist.

Jin's eyes widen, his jaw slackens beautifully, and Mugen grins. He wrenches hard, cracking Jin's back and throwing him down to the dirt in the moment of shock he had been afforded. Dirt mixes with sweat and bleeds in muddy streaks down Mugen's neck, falling out of his hair and into Jin's eyes. For an instant, the sunlight makes it a halo. Then Jin blinks against the sting in his eyes and fights the hold Mugen has on his wrists, trying not to gasp at the pain in his back. He fights toward the left, toward where Mugen is weak, but Mugen holds and bends the few inches it takes him to run his tongue along the line of Jin's jaw to the scabbing mess of his neck.

Mugen does not bite, although his teeth graze some of the healthier skin, but sucks at the end, drawing old blood into his mouth because he himself is not bleeding.

Jin bites his voice down and slides a sweat-slicked hand free of Mugen's grasp, beating the side of his head with the closest rock he can grab. He misses the temple by a lucky few centimeters but knocks the skin away and Mugen bleeds from the side of his head, unconscious on the ground. Jin shoves him off and lays prone, tentatively reaching back and testing the muscles he can reach. His back aches but the pain is dull and hot, the pain of blood and healing.

Jin takes the time to breathe, to calm himself, to wipe his neck and his face on his sleeve, to clean his glasses. He sits upright and watches Mugen, waits for the bruises under his eyes to begin to show, for him to groan and reach up and massage the side of his head.

While Jin waits, Mugen's blood pools on the ground, drying brittle over the sweat on his face.

* * *

Jin does not know when Mugen learned to read him.

"Relax. I'm exhausted as fuck."

So Jin does, leaning back against the rocks in the hot spring, and shuts his eyes. The heat does wonders for his muscles, and he is used to the smell. It is the closest thing to a bath he often manages, and the closest thing to a bath Mugen will ever get. He puts on the façade of dozing, listening to Mugen splash around, groan and hiss at the heat, and finally relax.

"You're not asleep."

Jin lets his mouth quirk at that one. "Of course not."

"Fucker. Using a rock."

"You removed my swords."

Mugen grumbles at that. Jin hears the soft splash of Mugen walking through the spring, feels the ripples in the water that signal his coming closer, and cracks open one eye. Mugen sits, across from Jin but hidden in the shadow of a rock, so his face is obscured.

Jin shifts, just a little, and lets the pain in his back show on his face because he is too relaxed, too tired.

"Broke your back." Mugen snorts.

"Broke your skull." Jin shifts again, seating himself a little further back and up so his headrest doesn't strain his neck.

"Couldn't if you tried."

"I wasn't trying."

"Could have fooled me."

"If I were trying, I would have killed you."

"'Sat how you're gonna say you won?"

Jin blinks lazily, following Mugen's thought pattern with a little more effort than he really cares to muster. "I always beat you."

"Nobody wins until the battle's actually over." Mugen idly flicks water with the ends of his fingers and the ripples die before they make it halfway across the pool.

"What do you call this?"

Mugen leans his head back and Jin can see the tendons working in his neck. "Rest break."

Jin leans his head back and looks at a completely different set of stars than Mugen, his view blurred by steam. After some time, when he can hear Mugen's breathing slow into a half-doze and the worst of his soreness has been melted by the heat, Jin speaks again. His voice is low and almost softer than the water.

"If I won by killing you, you would be trying to kill me in kind."

Mugen sits up, dunking his shoulders and raising an eyebrow. "What do you call winning?"

Jin gets up and walks out and away, wringing out the wet end of his ponytail.

"When you're silent."

* * *

Always they meet with a tinge of secrecy, purposefully muffling their movements and voices to protect Fuu from their fight, to become small enough not to warrant attention. It throws the adrenaline of exhibitionism into both their systems, and it is unspoken but agreed that neither of them should give the other away. For Mugen it is often harder, but Jin's silence is trained and easy.

Now, Mugen does not speak at all, and Jin knows the mockery intimately as his breath is knocked from him by a tree and Mugen's arms crossed over his chest. Jin punches Mugen in the face, throwing his head sideways. Mugen only gasps, licks his split lip, and drives his knee into Jin's thigh.

Jin growls for him, suddenly loosing his own throat, and Mugen catches his wrists with fever in his cheeks, his face breaking into an impossible grin. Mugen lets go of his own tongue and growls back, passionate as he traces Jin's pulse from collar to ear with tongue and teeth. Jin shudders, his fingers grasping at air and Mugen's hands burning around his wrists. Mugen bites below Jin's ear, then harder at the juncture of his neck and shoulder, releasing one hand to pull Jin's body better against his own.

Jin threads his fingers into Mugen's hair and yanks hard, trying to pull him away, but Mugen does not bend, shutting his eyes and sucking where he had bitten into Jin's skin hard enough to break it. Instead, with each tug, Mugen writhes against Jin, a fist in the small of his back forcing Jin to curve into the friction, until Jin sets his own sort of rhythm despite himself. He pulls harshly on Mugen's hair and Mugen responds, snarling at his neck and grinding against Jin.

Mugen lets go of Jin's other hand and grabs his ponytail, wrenching his head to the side so he can bite the other side of his neck, and as his teeth sink in Jin punches his throat hard in the same bruise around his Adam's Apple that refuses to heal.

Mugen spits blood and stumbles back, heaving for air. Jin shrugs his clothing back on, hiding the hot marks except for the perfect crescents below his ear, and frowns when Mugen's saliva smears. Mugen curls over himself, managing to maintain his feet but dripping blood, sweat, spit, mud, tears from the pain, and his breathing is harsher than the first time Jin attacked his throat.

Jin waits it out, forcing his body to calm and not betray him, pushing his appalled disgust at himself to the back of his mind to be dealt with when he can manage it. His neck is sore and he focuses on that to bring some sense back, to clear his vision, to forget the sound of himself when he growls.

Mugen does not straighten for a long time, breathing with his eyes wide open and his hands around his throat. When he does, a keening groan escapes him and the blood on his teeth is not from his split lip.

Jin acknowledges it, walking past and not looking over at the dark blotch under Mugen's chin.

"Draw."

* * *

It takes Mugen three days. Mainly because Fuu managed to get herself kidnapped again and he and Jin were caught up in saving her, and partly because he could barely speak without his throat aching to holy hell. Mugen is cleverer than he is given credit, though, and when he trusts his body to take Jin on again, it is on the evening of the fourth day, while Fuu is bathing and commiserating with, of all things, a squirrel.

"What did you mean, 'draw'?"

Jin, his swords resting against his shoulder as he sits with perfect posture against the wall, looks up and his glasses shield his eyes. "What?"

"You called it a draw." Mugen leans against the opposite wall, his knees drawn up lazily and his elbows resting on them. The shadows almost camouflage his healing bruise, and his voice is almost as full as it had been. "You won halfway and I won halfway."

"That is not the definition of a draw."

Mugen raises an eyebrow, canting his head slightly. "Then you called it wrong, didn't you?" He pauses, just sitting and appraising and, for the first time Jin's ever seen, analyzing.

There is a grin in his voice. "How's your neck?"

Jin frowns severely, resisting the urge to put his hand over the darkest and most permanent of the marks Mugen left. "Be quiet."

"I was. Your half of the draw." Mugen lets one of his knees slip to the floor, and curls his arm into his lap, lazy fingers resting on the inside of his knee. "Tell me mine."

When Jin does not answer, glaring through the protective shine on his glasses, Mugen laughs, low and slick and rumbling. He moves quickly onto his knees, between Jin's knees, with his hands propped on the floor at Jin's hips. "You _liked_ it. You'd never let it continue if you didn't."

Jin rears and punches but Mugen catches his hand. And the other. He pushes them up and over Jin's head against the wall, and without the cup of his shoulders, Jin's swords clatter out of his lap and to the floor. Jin looks down to them, frowning more fiercely, and Mugen takes that moment to pull Jin's hakama away from his neck and bite down on the old bruise, laughing when Jin moans despite himself.

Jin kicks out, lashing for Mugen's groin, and the heel of his sandal meets something hard. The sound of impact resonates, and though Mugen jumps he doesn't rear back in pain. Instead he laughs harder, reaching down into his pants and pulling out a ceramic bowl.

Jin stares at it for a moment, entirely dumbfounded. And then, because of the entirety of his surprise, he laughs too, closing his eyes. Mugen rumbles, chuckling and enjoying the sound of Jin's laughter.

Jin lashes out, aiming for Mugen's groin. This time he connects.

Jin is still smirking when Mugen manages to recover, and his laughter resurfaces when Mugen jams the bowl back down into his pants, swearing profusely.

"Take it out. You look ridiculous."

"Like hell you care about me looking ridiculous."

"More ridiculous than usual. You'll draw unwanted attention."

Mugen snorts and grabs the bowl, spinning it on his finger before pitching it at Jin's head. Jin brings a sword up and catches it on the end of the sheath. He recognizes the artwork and sighs a little.

"You stole this _today_. I always supposed you were a slow learner but I never realized how slow you truly were."

Mugen growls and swipes the bowl back, rolling it over his knuckles. "You tryin' to start a fight?"

"A real one?" Jin challenges.

When Mugen has to pause to consider, Jin continues "Not now. Belligerent fool."

Fuu pokes her head into the room. "Have you guys seen— what's that?"

Mugen spins the bowl on his finger and then tosses it to her, grinning crookedly when she catches it.

Fuu examines the bowl, holding it in both hands, and raises her eyebrows, throwing it back at Mugen. "You stole that from the last restaurant! What the heck are you going to do with a bowl, you jerk? You thief! Nobody's going to want that if you even try to _pawn_ it; it's too dirty!" She clenches her fists by her sides and stomps away. "I'll find it on my own, and I'll see you two _thieves_ in the morning."

As soon as her footsteps fade, Mugen collapses onto the floor, laughing so hard he has to grab at his throat and calm himself down.

Jin snorts. "That was uncalled-for."

"She wanted to see the bowl!" Mugen grins like a jackal. "Think I can get her to drink from it?"

Jin holds out a hand. "Give it here."

Mugen throws the bowl to him, still grinning. Jin neatly pitches it out of the room, where it smashes into shards against a boulder. Mugen frowns. "Hey!"

Jin replaces his swords in his lap and leans against the wall. "Fuu was right; that bowl was worthless to us."

"How worthless?"

"Entirely."

"Fuck you."

Jin does not rise to the bait, and instead bows his head, ending the conversation.

* * *

Mugen nurses a bleeding nose and Jin sucks on a split lip. The taste of Mugen's breath fills the cut and Jin curbs the urge to spit. In with the blood is booze and dirt and decay, the contents of Mugen's guts fermented with exertion in the outdoors.

Fuu is yelling. They ignore her, as Jin pulls himself to his feet and Mugen scrambles to do likewise, eyes locked on one another's faces. Mugen's fingers flex; Jin's tongue flicks out, probing at the end of his cut.

"Excuse us," Jin whispers, and Mugen is already off running. He heads in a different direction, leaving Fuu torn between which of them to chase and shouting about their promise to her.

Jin runs until Mugen finds him and throws him on the far side of a boulder, sending leaves and dirt flying downhill below them. Jin's breath is knocked from him but he responds to Mugen's teeth on his lip by pulling hard on his hair. When he gets his knee between Mugen's legs and jerks, Mugen jumps away, then growls at Jin's trick, biting him for his trouble. Jin laughs, biting back, and Mugen shudders into his hands.

Neither of them can hear Fuu coming yet, neither knows whether he was the one she chose to follow or if she followed at all.

If pressed, Mugen will use that as his reasoning for staying nearly silent as Jin.


End file.
